1. Field of the Invention
This invention relates to a film-forming polymer. More particularly, it relates to a polymer useful for a permselective membrane.
2. Description of the Prior Art
As the materials for producing permselective membranes, there have been known heretofore several polymers. For example, polydimethylsiloxanes and copolymers thereof with polycarbonates or others have been disclosed (U.S. Pat. Nos. 3,980,456, and 3,874,986; and Japan Patent Lay-open No. 26504/1981). Olefin polymers such as poly-4-methylpentene-1 have also been disclosed (Japan Patent Lay-open No. 4203/1982). However, these polymers can not fulfill all the fundamental requirements needed, for use as permselective membranes, namely good permeability and selectivity as well as processability to form thin film.